Valve.



C.R.BALLARD.

VALVE.

APPLICATION FILED MAILS. 1911.

1,022, 171 Patented Apr. 2, 1912.

Fly 3.

WITNESSES ,JWO /6 2 4 9 All'y,

COLUMBIA PLANOORAPN (IO-.WAshlNuroN. D. C

CHARLES R. BALLARID, O13 MIDWAY, PENNSYLVANIA.

Specification of Letters Patent.

Patented Apr. 2, 1912.

Application filed March 3, 1911. Serial No. 611,969.

T 0 all whom it may concern:

Be it known that I, CHARLES It. BALLARD, a resident of Midway, in thecounty of Washington and State of Pennsylvania, have invented a new anduseful Improvement in Valves, of which the following is a specification.

This invention relates to valves for compressors, pumps and the like,and more particularly to outlet valves therefor, although the mainfeatures are also applicable to inlet valves.

The object of the invention is to provide for the purposes stated avalve of simple and durable construction, one which is noiseless in itsaction, which is so constructed that it can be easily attached to andremoved from the cylinder head, and which is so con structed as toprotect the spring and other portions from the dirt or grit in the fluidbeing compressed or pumped.

The invention comprises a valve constructed and arranged as hereinafterdescribed and claimed.

In the accompanying drawing Figure 1 is a longitudinal sectional viewthrough the valve showing it attached to the cylinder head; Fig. 2 is atransverse section on the line 22, Fig. 1; and Fig. 3 is a centrallongitudinal section of a portion of the valve showing a modification.

In the drawing 1 indicates a portion of the head of a cylinder of an aircompressor or similar apparatus.

The valve is shown as an outlet valve and comprises a casing 2 which atits inner end is open to the pump or compressor cylinder and is providedwith a seat 3 with which cooperates valve 4. The latter is of hollowcylindrical construction, as shown, with its side walls 5 having a closesliding fit in the chamber in casing 2. The chamber in casing 2 issomewhat enlarged at its outer end to form a piston chamber 6, and theouter end of valve shell 5 is enlarged to form in effect a piston orhead 7 having a fairly close fit in the chamber 6 in the casing andforming therewith a dashpot. The piston 7 may if desired be providedwith a packing ring, or with packing grooves shown at S. It may also, ifdesired, be provided with a port 9 extending therethrough to allow airto pass from one face to the other thereof. Obviously the piston 7working in chamber 6 steadies the movement of valve 4 and prevents thesame from closing so suddenly as to cause disagreeable noises. The valveis provided with a large cylindrical projection extending inwardly intothe opening to the compressor cylinder to reduce clearance to a minimum.

The valve is normally held to its seat by means of spring 10 which isentirely inclosed within the hollow valve and therefore protected fromthe dirt or grit in the fluid being compressed or pumped and not liableto clog or become foul thereby. This spring at its inner end bearsdirectly against valve 4t, and at its outer end bears against the outerend of the hollow portion in stem 11 projecting inwardly from the cap 12which closes the outer end of the casing, being threaded therein asshown. The outlet or inlet ports 13 are in the sides of the casing nearits inner end.

Fig. piston 7 instead of being integral with the shell 5 of the valve isadjustable thereon, such as having a threaded connection therewith, asshown at 14, so as to permit said piston to be moved to variouspositions longitudinally on the valve and vary the extent of openingmovement of the valve, which is limited by contact of piston 7 with theinner face 15 of the cap 12. In this case also the spring 10 surroundsthe stem 11 and has its outer end bearing against shoulder 16 on saidstem. In order to lock the piston 7 on the stem and prevent accidentalrotation thereon I provide a key 18, preferably threaded into a holeformed partly in the piston 7 and partly in the shell 5 of the valve. Inthis case also the piston is preferably provided in its outer face witha pair of recesses 19 for receiving a spanner wrench or similar tool forturning the same on the valve stem to adjust it thereon. The cap 12 isalso provided with recesses 20 for a similar purpose. The casing 2 isthreaded at its inner end, as at 22, and is secured to the cylinder headby merely screwing it into a threaded opening therein.

The valve described is of solid compact construction and is supportedentirely at its inner end, thereby dispensing with the usual complicatedarrangement for fastening the valve to or in the cylinder head. Thevalve is entirely self-contained, and can be assembled and adjusted atthe factory and in the field can be attached to the compressor or pumpby any ordinary mechanic. has much as it is self-contained it can be re-3 shows a modification wherein the moved from the pump and a new oneplaced thereon in a very short period of time thereby reducing the timenecessary to shut down the compressor or pump. The valve is composed ofa minimum number of parts which are all strong and of very simple shapeso that breakage or derangement is not likely. The large cylindricalvalve presents a large wearing surface so that wear is verly largelyreduced, and the spring is entirely housed in the valve proper so thatit cannot be fouled or clogged by the dirt or other impurities in thefluid being compressed or pumped.

The valve described obviously can be adapted for an inlet valve as wellas for an outlet valve.

What I claim is:

1. A self-contained outlet valve for compressors, pumps and the like,comprising a cylindrical one-piece casing having a bore enlarged at itsouter end to form a piston chamber, said casing being provided at itsinner end with means for attachment to a cylinder head and adjacentthereto with a valve seat and having ports through its side walls, avalve comprising a cylinder having its inner end closed to cooperatewith said valve seat, said cylinder having a close sliding fit in saidbore and being enlarged at its outer end to form a piston having a closesliding fit in said piston chamber and being provided with a restrictedpassage leading from one face of the piston tothe other, a cap fittingin the outer open end of the bore to close the latter, said cap having areduced central stem projecting inwardly into said bore, and a spiralspring seated between said stem and valve to seat the latter.

2. A self-contained valve for compressors, pumps and the like,comprising a onepiece cylindrical casing having a reduced forward endprovided with screw threads for connection to a cylinder head, wherebythe valve projects bodily from the cylinder head, said casing beingprovided with a bore reduced at its forward end to form a valve seat andenlarged at its rear end to form a piston chamber and provided to therear of said seat with ports through its side walls, a valve comprisinga hollow cylinder having a close sliding fit in said bore, said cylinderbeing closed at its forward end and formed to cooperate with the valveseat and enlarged at its rear end to form a piston sliding in saidpiston chamber, a cap secured to the outer end of said casing to closethe latter, said cap having a stem projecting into said hollow cylinder,and a spiral spring seated in said hollow cylinder and engaging saidstem and arranged to seat said valve, said valve having a reducedforward end substantially filling said bore to reduce clearance.

3. A self-contained valve for compressors, pumps and the like,comprising a onepiece casing provided at one end with means forattachment to a cylinder head and provided with a bore and ports throughits side walls, said bore forwardly of said ports being formed with avalve seat and being enlarged at its rear end to form a piston chamber,a valve in said casing comprising a hollow cylinder having one endclosed and formed to cooperate with said seat and being enlarged at itsrear end to form a piston having a close sliding fit in said chamber, acap screwed into the outer end of said casing and having a reducedhollow stem projecting forwardly into said cylinder, and a spiralcompression spring seated in said hollow cylinder and hollow stem andarranged to seat said valve.

In testimony whereof, I have hereunto set my hand.

CHARLES R. BALLARD.

Witnesses:

F. W. WINTER, MARY E. GAHooN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. (3.

